Conventionally, there has been disclosed a power conversion apparatus that performs power conversion using a switching circuit including a semiconductor switch such as an IGBT. For example, as the power conversion apparatus, there has been disclosed a voltage-type inverter that converts a DC voltage into an AC voltage using a switching circuit and outputs the AC voltage.
In the power conversion apparatus, a smoothing capacitor is provided between a DC power source and the switching circuit to smooth a voltage (for example, refer to Japanese Patent Laid-Open Publication No. 2007-221892). The smoothing capacitor is called a main circuit capacitor and is connected to the switching circuit through a bus bar.
However, for example, a high frequency ripple current and the like flow through the bus bar that connects the main circuit capacitor to the switching circuit, causing heat by a skin effect. Furthermore, as the length of the bus bar increases, impedance in a high frequency region should be considered and eventually becomes a main factor that generates a surge voltage at the time of switching of the switching circuit.
In this regard, it is preferable to shorten the length of the bus bar that connects the main circuit capacitor to the switching circuit.